src/share/classes/java/lang/invoke/InnerClassLambdaMetafactory.java
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@@ -23,29 +23,26 @@
* questions.
*/
package java.lang.invoke;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.Method;
+import java.security.ProtectionDomain;
+import java.util.concurrent.atomic.AtomicInteger;
import jdk.internal.org.objectweb.asm.*;
+import static jdk.internal.org.objectweb.asm.Opcodes.*;
import sun.misc.Unsafe;
-
-import java.lang.reflect.Constructor;
import java.security.AccessController;
import java.security.PrivilegedAction;
-import java.security.ProtectionDomain;
-import java.util.concurrent.atomic.AtomicInteger;
-import static jdk.internal.org.objectweb.asm.Opcodes.*;
-
/**
* Lambda metafactory implementation which dynamically creates an inner-class-like class per lambda callsite.
*
* @see LambdaMetafactory
*/
/* package */ final class InnerClassLambdaMetafactory extends AbstractValidatingLambdaMetafactory {
- private static final Unsafe UNSAFE = Unsafe.getUnsafe();
-
private static final int CLASSFILE_VERSION = 51;
private static final String METHOD_DESCRIPTOR_VOID = Type.getMethodDescriptor(Type.VOID_TYPE);
private static final String NAME_MAGIC_ACCESSOR_IMPL = "java/lang/invoke/MagicLambdaImpl";
private static final String NAME_CTOR = "<init>";
@@ -78,55 +75,40 @@
private final String[] argNames; // Generated names for the constructor arguments
private final String lambdaClassName; // Generated name for the generated class "X$$Lambda$1"
private final Type[] instantiatedArgumentTypes; // ASM types for the functional interface arguments
/**
- * General meta-factory constructor, supporting both standard cases and
- * allowing for uncommon options such as serialization or bridging.
+ * General meta-factory constructor, standard cases and allowing for uncommon options such as serialization.
*
- * @param caller Stacked automatically by VM; represents a lookup context
- * with the accessibility privileges of the caller.
- * @param invokedType Stacked automatically by VM; the signature of the
- * invoked method, which includes the expected static
- * type of the returned lambda object, and the static
- * types of the captured arguments for the lambda. In
- * the event that the implementation method is an
- * instance method, the first argument in the invocation
- * signature will correspond to the receiver.
- * @param samMethod The primary method in the functional interface to which
- * the lambda or method reference is being converted,
- * represented as a method handle.
- * @param implMethod The implementation method which should be called (with
- * suitable adaptation of argument types, return types,
- * and adjustment for captured arguments) when methods of
- * the resulting functional interface instance are invoked.
- * @param instantiatedMethodType The signature of the primary functional
- * interface method after type variables are
- * substituted with their instantiation from
- * the capture site
- * @param isSerializable Should the lambda be made serializable? If set,
- * either the target type or one of the additional SAM
- * types must extend {@code Serializable}.
- * @param markerInterfaces Additional interfaces which the lambda object
- * should implement.
- * @param additionalBridges Method types for additional signatures to be
- * bridged to the implementation method
+ * @param caller Stacked automatically by VM; represents a lookup context with the accessibility privileges
+ * of the caller.
+ * @param invokedType Stacked automatically by VM; the signature of the invoked method, which includes the
+ * expected static type of the returned lambda object, and the static types of the captured
+ * arguments for the lambda. In the event that the implementation method is an instance method,
+ * the first argument in the invocation signature will correspond to the receiver.
+ * @param samMethod The primary method in the functional interface to which the lambda or method reference is
+ * being converted, represented as a method handle.
+ * @param implMethod The implementation method which should be called (with suitable adaptation of argument
+ * types, return types, and adjustment for captured arguments) when methods of the resulting
+ * functional interface instance are invoked.
+ * @param instantiatedMethodType The signature of the primary functional interface method after type variables
+ * are substituted with their instantiation from the capture site
+ * @param flags A bitmask containing flags that may influence the translation of this lambda expression. Defined
+ * fields include FLAG_SERIALIZABLE.
+ * @param markerInterfaces Additional interfaces which the lambda object should implement.
* @throws ReflectiveOperationException
- * @throws LambdaConversionException If any of the meta-factory protocol
- * invariants are violated
+ * @throws LambdaConversionException If any of the meta-factory protocol invariants are violated
*/
public InnerClassLambdaMetafactory(MethodHandles.Lookup caller,
MethodType invokedType,
MethodHandle samMethod,
MethodHandle implMethod,
MethodType instantiatedMethodType,
- boolean isSerializable,
- Class<?>[] markerInterfaces,
- MethodType[] additionalBridges)
+ int flags,
+ Class<?>[] markerInterfaces)
throws ReflectiveOperationException, LambdaConversionException {
- super(caller, invokedType, samMethod, implMethod, instantiatedMethodType,
- isSerializable, markerInterfaces, additionalBridges);
+ super(caller, invokedType, samMethod, implMethod, instantiatedMethodType, flags, markerInterfaces);
implMethodClassName = implDefiningClass.getName().replace('.', '/');
implMethodName = implInfo.getName();
implMethodDesc = implMethodType.toMethodDescriptorString();
Type implMethodAsmType = Type.getMethodType(implMethodDesc);
implMethodArgumentTypes = implMethodAsmType.getArgumentTypes();
@@ -150,12 +132,11 @@
* which will call the class' constructor.
*
* @return a CallSite, which, when invoked, will return an instance of the
* functional interface
* @throws ReflectiveOperationException
- * @throws LambdaConversionException If properly formed functional interface
- * is not found
+ * @throws LambdaConversionException If properly formed functional interface is not found
*/
@Override
CallSite buildCallSite() throws ReflectiveOperationException, LambdaConversionException {
final Class<?> innerClass = spinInnerClass();
if (invokedType.parameterCount() == 0) {
@@ -191,20 +172,12 @@
/**
* Generate a class file which implements the functional
* interface, define and return the class.
*
- * @implNote The class that is generated does not include signature
- * information for exceptions that may be present on the SAM method.
- * This is to reduce classfile size, and is harmless as checked exceptions
- * are erased anyway, no one will ever compile against this classfile,
- * and we make no guarantees about the reflective properties of lambda
- * objects.
- *
* @return a Class which implements the functional interface
- * @throws LambdaConversionException If properly formed functional interface
- * is not found
+ * @throws LambdaConversionException If properly formed functional interface is not found
*/
private Class<?> spinInnerClass() throws LambdaConversionException {
String samName = samBase.getName().replace('.', '/');
String[] interfaces = new String[markerInterfaces.length + 1];
interfaces[0] = samName;
@@ -222,26 +195,32 @@
fv.visitEnd();
}
generateConstructor();
+ MethodAnalyzer ma = new MethodAnalyzer();
+
// Forward the SAM method
- String methodDescriptor = samMethodType.toMethodDescriptorString();
- MethodVisitor mv = cw.visitMethod(ACC_PUBLIC, samInfo.getName(), methodDescriptor, null, null);
- new ForwardingMethodGenerator(mv).generate(methodDescriptor);
+ if (ma.getSamMethod() == null) {
+ throw new LambdaConversionException(String.format("Functional interface method not found: %s", samMethodType));
+ } else {
+ generateForwardingMethod(ma.getSamMethod(), false);
+ }
// Forward the bridges
- if (additionalBridges != null) {
- for (MethodType mt : additionalBridges) {
- methodDescriptor = mt.toMethodDescriptorString();
- mv = cw.visitMethod(ACC_PUBLIC|ACC_BRIDGE, samInfo.getName(), methodDescriptor, null, null);
- new ForwardingMethodGenerator(mv).generate(methodDescriptor);
+ // @@@ The commented-out code is temporary, pending the VM's ability to bridge all methods on request
+ // @@@ Once the VM can do fail-over, uncomment the !ma.wasDefaultMethodFound() test, and emit the appropriate
+ // @@@ classfile attribute to request custom bridging. See 8002092.
+ if (!ma.getMethodsToBridge().isEmpty() /* && !ma.conflictFoundBetweenDefaultAndBridge() */ ) {
+ for (Method m : ma.getMethodsToBridge()) {
+ generateForwardingMethod(m, true);
}
}
- if (isSerializable)
+ if (isSerializable) {
generateWriteReplace();
+ }
cw.visitEnd();
// Define the generated class in this VM.
@@ -266,11 +245,11 @@
return targetClass.getProtectionDomain();
}
}
);
- return UNSAFE.defineClass(lambdaClassName, classBytes, 0, classBytes.length,
+ return (Class<?>) Unsafe.getUnsafe().defineClass(lambdaClassName, classBytes, 0, classBytes.length,
loader, pd);
}
/**
* Generate the constructor for the class
@@ -284,12 +263,11 @@
int lvIndex = 0;
for (int i = 0; i < argTypes.length; i++) {
ctor.visitVarInsn(ALOAD, 0);
ctor.visitVarInsn(argTypes[i].getOpcode(ILOAD), lvIndex + 1);
lvIndex += argTypes[i].getSize();
- ctor.visitFieldInsn(PUTFIELD, lambdaClassName, argNames[i],
- argTypes[i].getDescriptor());
+ ctor.visitFieldInsn(PUTFIELD, lambdaClassName, argNames[i], argTypes[i].getDescriptor());
}
ctor.visitInsn(RETURN);
ctor.visitMaxs(-1, -1); // Maxs computed by ClassWriter.COMPUTE_MAXS, these arguments ignored
ctor.visitEnd();
}
@@ -303,11 +281,11 @@
NAME_METHOD_WRITE_REPLACE, DESCR_METHOD_WRITE_REPLACE,
null, null));
mv.visitCode();
mv.visitTypeInsn(NEW, NAME_SERIALIZED_LAMBDA);
- mv.visitInsn(DUP);
+ mv.visitInsn(DUP);;
mv.visitLdcInsn(Type.getType(targetClass));
mv.visitLdcInsn(samInfo.getReferenceKind());
mv.visitLdcInsn(invokedType.returnType().getName().replace('.', '/'));
mv.visitLdcInsn(samInfo.getName());
mv.visitLdcInsn(samInfo.getMethodType().toMethodDescriptorString());
@@ -333,39 +311,57 @@
mv.visitMaxs(-1, -1); // Maxs computed by ClassWriter.COMPUTE_MAXS, these arguments ignored
mv.visitEnd();
}
/**
+ * Generate a method which calls the lambda implementation method,
+ * converting arguments, as needed.
+ * @param m The method whose signature should be generated
+ * @param isBridge True if this methods should be flagged as a bridge
+ */
+ private void generateForwardingMethod(Method m, boolean isBridge) {
+ Class<?>[] exceptionTypes = m.getExceptionTypes();
+ String[] exceptionNames = new String[exceptionTypes.length];
+ for (int i = 0; i < exceptionTypes.length; i++) {
+ exceptionNames[i] = exceptionTypes[i].getName().replace('.', '/');
+ }
+ String methodDescriptor = Type.getMethodDescriptor(m);
+ int access = isBridge? ACC_PUBLIC | ACC_BRIDGE : ACC_PUBLIC;
+ MethodVisitor mv = cw.visitMethod(access, m.getName(), methodDescriptor, null, exceptionNames);
+ new ForwardingMethodGenerator(mv).generate(m);
+ }
+
+ /**
* This class generates a method body which calls the lambda implementation
* method, converting arguments, as needed.
*/
private class ForwardingMethodGenerator extends TypeConvertingMethodAdapter {
ForwardingMethodGenerator(MethodVisitor mv) {
super(mv);
}
- void generate(String methodDescriptor) {
+ void generate(Method m) throws InternalError {
visitCode();
if (implKind == MethodHandleInfo.REF_newInvokeSpecial) {
visitTypeInsn(NEW, implMethodClassName);
- visitInsn(DUP);
+ visitInsn(DUP);;
}
for (int i = 0; i < argTypes.length; i++) {
visitVarInsn(ALOAD, 0);
visitFieldInsn(GETFIELD, lambdaClassName, argNames[i], argTypes[i].getDescriptor());
}
- convertArgumentTypes(Type.getArgumentTypes(methodDescriptor));
+ convertArgumentTypes(Type.getArgumentTypes(m));
// Invoke the method we want to forward to
visitMethodInsn(invocationOpcode(), implMethodClassName, implMethodName, implMethodDesc);
// Convert the return value (if any) and return it
// Note: if adapting from non-void to void, the 'return' instruction will pop the unneeded result
- Type samReturnType = Type.getReturnType(methodDescriptor);
+ Type samReturnType = Type.getReturnType(m);
convertType(implMethodReturnType, samReturnType, samReturnType);
visitInsn(samReturnType.getOpcode(Opcodes.IRETURN));
visitMaxs(-1, -1); // Maxs computed by ClassWriter.COMPUTE_MAXS, these arguments ignored
visitEnd();